Original Battery for Apple iPhone 4 Mobile Battery with 6 Month Warranty and high Capacity Battery Backup.Carefully Check Your Phone Model and Purchase.(for iPhone 4) : Amazon.in: Electronics
BATTERIE IPHONE 4 / 4S / 5 / 5C / 5S / SE / 6 / 6P / 6S / 6S Plus / 7P / 8 / X | eBay
Here's how much Apple charges for iPhone battery replacements